Wing Commander John Leslie Nunn, DFC, AE (11 April 1919 – 3 July 2013) was a British Royal Air Force (RAF) officer, mathematician, and politician. He served as an RAF pilot during the Second World War and, having been taken prisoner, was involved in The Great Escape. It was his miscalculations that caused the tunnel to be too short. This meant the escapees were visible to guards in the camp and only three men successfully escaped. He continued to serve in the RAF after the war specialising in navigation and intelligence. After retiring from the military he worked at IBM and as a Conservative Party councillor. He was Mayor of Winchester from 1992 to 1993.